1. Field of the invention
The present invention relates to an apparatus for writing and/or reading binary information on a flexible magnetic disc, comprising a rotatable hub adapted to engage with the disc and a writing and/or reading head mounted at the end of an arm which so moves in synchronism with the hub so as to move the head generally radially with respect to the hub. The arm may be pivoted so that the head follows an arcuate path which is nevertheless generally radial with respect to the hub. The apparatus is particularly suitable for use with the smaller size flexible discs now employed for some purposes and having a diameter less than 100 mm.
2. Description of the prior art
An apparatus of the type referred to is known wherein the hub is provided with a radial element engaging with the disc to rotate with it and wherein the disc is set in rotation by a pair of opposed rollers, which nip the disc and one of which is connected to an electric motor; in this way, therefore, it is the hub that is driven by the disc. In this apparatus, a worm is formed on the hub and engages with a worm wheel connected in turn to a screw which, by engaging with a lead nut, controls the radial movement of the writing head in synchronism with the rotation of the disc and the hub.
This apparatus, however, has the disadvantage that the magnetic disc is directly coupled to the rollers and is therefore subject to considerable wear in the part in contact with them, moreover, the synchronization between the head and the disc suffers from the effects of the inevitable backlash in the worm and worm wheel and the control screw and lead nut.